A. cannot be nestedB. manipulate data itemsC. act on ea……

单项选择题Which describes the default behavior when you create a table? （）

A. The table is accessible to all users.
B. Tables are created in the public schema.
C. Tables are created in your schema.
D. Tables are created in the DBA schema.
E. You must specify the schema when the table is created.

单项选择题The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) The registrar requested a report listing the students grade point averages (GPA) sorted from highest grade point average to lowest. Which statement produces a report that displays the student ID and GPA in the sorted order requested by the registrar? （）

A. SELECT student_id, gpa FROM student_grades ORDER BY gpa ASC;
B. SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa ASC;
C. SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa;
D. SELECT student_id, gpa FROM student_grades ORDER BY gpa;
E. SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa DESC;
F. SELECT student_id, gpa FROM student_grades ORDER BY gpa DESC;

单项选择题You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?（）

A. ALTER TABLE students ADD PRIMARY KEY _ id;
B. ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);
C. ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;
D. ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
E. ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);

单项选择题You are the DBA for an academic database. You need to create a role that allows a group of users to modify existing rows in the STUDENT_GRADES table. Which set of statements accomplishes this? （）

A. CREATE ROLL registrar; GRANT MODIFY ON student_grant TO registrar; GRANT registrar to user 1, user2, user3
B. CREATE NEW ROLE registrar; GRANT ALL ON student_grant TO registrar; GRANT registrar to user 1, user2, user3
C. CREATE ROLL registrar; GRANT UPDATE ON student_grant TO registrar; GRANT ROLE to user1, user2, user3
D. CREATE ROLL registrar; GRANT UPDATE ON student_grant TO registrar; GRANT registrar to user 1, user2, user3;
E. CREATE registrar; GRANT CHANGE ON student_grant TO registrar; GRANT registrar;

单项选择题Evaluate this SQL statement: SELECT ename, sal, 12* sal+100 FROM emp; The SAL column stores the monthly salary of the employee. Which change must be made to the above syntax to calculate the annual compensation as monthly salary plus a monthly bonus of $100, multiplied by 12 ? （）

A. No change is required to achieve the desired results.
B. SELECT ename, sal, 12* (sal+100) FROM emp;
C. SELECT ename, sal, (12* sal)+100 FROM emp;
D. SELECT ename, sal +100,*12 FROM emp;